Today’s decision in R. v. National Post, 2010 SCC 16 (CanLII) contains the following line from Binnie J for the majority (McLachlin C.J. and Binnie, Deschamps, Fish, Charron, Rothstein and Cromwell JJ.:
As recently pointed out in Grant v. Torstar Corp., 2009 SCC 61,  3 S.C.R. 640, the protection attaching to freedom of expression is not limited to the “traditional media”, but is enjoyed by “everyone” (in the words of s. 2(b) of the Charter) who chooses to exercise his or her freedom of expression on matters of public interest whether by blogging, tweeting, standing on a street corner and shouting the “news” at passing pedestrians or publishing in a national newspaper. To throw a constitutional immunity around the interactions of such a heterogeneous and ill-defined group of writers and speakers and whichever “sources” they deem worthy of a promise of confidentiality and on whatever terms they may choose to offer it (or, as here, choose to amend it with the benefit of hindsight) would blow a giant hole in law enforcement and other constitutionally recognized values such as privacy.